there are 4 diagnostic leds(abcd) on the back of the system what color are they? this will give us a code we can look up on dells website that will usually indicate where the problem is.
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Browse All TopicsI have a Dell Dimension 4300 that died. Got a new power supply from Dell and a new system board. After replacing both of these I do now get power and the hard drives spin up but I don't get any POST screen, beep codes, and the monitor doesn't seem like it's recieving a signal from the pc. I swapped out a video card, no change. I swapped processors, no change. I re-seated all cables, no change? Not sure what else there would be to do to fix this.
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Sounds like this is a hardware issue of some sort and the fact that you don't have a "POST screen, beep codes, and the monitor doesn't seem like it's recieving a signal from the PC" would tend to make me think something wrong or related to the motherboard. Good ideas are Callandor with checking the RAM and 4 Pin Power Connector. An inspection to insure everything is properly connected and even reseating the connections might be good. Additionally, jamietoner idea to check the 4 Diagnostic Leds on the back of the CPU is a good idea. They provide an internal test and all should be Green. If any are Amber or not lit this this is an indication a problem exist. Providing the light sequence will point a direction to pursue.
Another thought is to be sure the motherboard is properly installed and not touching the case. (i.e. shorting out.) Could try removing everything from the board (HD, Memory, Video Card, etc.) and only have the motherboard and Power supply connected. It will not boot but should give a Beep Code. If a Beep Code is given, start replacing parts begining with the memory until you find the problem. If no Beep Code is given then the Power Supply or Motherboard is the likely source of your issue.
Hope this Helps!!!
Per the Dell Manual for the Dimension 4300:
Diagnostic Code: No Diagnostic lights on the Back of the CPU.
Definition: Power Up Default
Corrective Action:
"Make sure that the computer is connected to a known working electrical outlet, and then check whether the front-Panel power light on the power button is on or off. If the power light is off, check the power supply. If the problem persists, see 'Contacting Dell' in the Solutions Guide for instructions on obtaining technical assistance."
Basically what you are likely looking at is either a bad power supply or a bad motherboard. You indicated an amber light is on the motherboard so I'd lean towards a motherboard issue.
Link to the Dimension 4300 Manual:
http://support.dell.com/su
Hope this Helps!!!
I think this relates to the CPU itself. Check that this is seated properly. I've seen Dell Optiplex's where it's just needed a firm push down on the heatsink to get them to boot nicely. Otherwise - remove the cpu and check for bent pins. If any are bent (probaby flat :-[ ), try restraightening GENTLY with needlenose pliers or tweezers.
Do you get any beeps if you boot with the memory removed?
hth,
Danny
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by: CallandorPosted on 2006-06-07 at 07:28:15ID: 16852592
Change the RAM for ones that you know work. Make sure if you have a separate 4-pin power connector that it is plugged into the motherboard.